no spark?

[knightrider]

just finished changing out the passenger side exhaust manifold due to it being badly cracked. that went rather smooth, until I tried to starting it. seemed to take a long time to finally crank.
next day would not start, now it cranks, gets fuel, but no spark. I did swap out a older flame thrower coil for a new one. old one seemed to read 6-7ohms which seemed high? still no go. I do have the petronix ignitor.
would(could) the ignition switch itself cause no spark? I vaguely remember having a similar issue with the original one 15plus years ago. also coincidently the dome light stopped working a month ago too!

thanks for any insight!!

[jopizz]

Put a test light on the + terminal of the coil and crank the engine. If it lights then you are getting power to the coil and it's not a switch problem. If it doesn't light you will have to trace the wire from the coil to the solenoid and the switch.

John

[knightrider]

no spark

ok light did light on + side of coil. went back through some connections and all seem good, tight not corroded etc.

[Tbird1044]

Johnny:
Your comments about taking a long time crank and next day would not start concern me. It almost sounds like your battery could be low or weak causing low voltage to the Pertronix and no spark. If it's cranking slowly, you might try throwing a set of jumper cables on and then try that. BTW, did you remove the resistor wire to the coil when you installed the Pertronix?
Nyles

[jopizz]

I agree with Nyles. Make sure your battery is fully charged. If you have a voltmeter put it on the + terminal of the coil and check it with both the car cranking and the key in the ON position. I believe the Pertronix ignition needs full 12V to work.

John

[sidewalkman]

ok light did light on + side of coil. went back through some connections and all seem good, tight not corroded etc.

Did you pull a lead and test it for spark? Easiest just pull a plug and hold it near ground, should arc across

[Hogan]

Which Pertronix module do you have (I, II, or III)?

[c4clewis]

What sidewalkman said. If you dont have a spark, check the battery and make sure you have at least 10v while cranking. The petronix wont fire with much less than 10. If your battery is good, it's likely the petronix module, I've had 1 or 2 go bad on me. 1 was only a partial failure under load and it was a PITA the figure out.

[knightrider]

no spark.

I am currently running the ignitor 2. I did have a spare plug which used to check spark or lack of
my battery was starting to wear down. I did have it on the charger for a night . I did getting 12v at the coil and resistor on the firewall.

so should I have removed that resistor which is on the firewall? + side goes to the resistor and not quite sure what the other connection goes too.
thanks for all the helpful suggestions!!

[jopizz]

When you crank the engine it bypasses the resistor and gets full 12V from the solenoid so I doubt that's your problem. You should bypass the resistor anyway as it needs full 12V to run correctly. You can just remove the wires and connect them together.

John

[knightrider]

no spark

Ok had the car taken into a local shop here for the "no spark " issue.
turned out to be a broken plate on the distr. They removed and had it rebuilt locally and reinstalled. all seems good now!

this was just after I got done replacing the passenger side exhaust manifold that had a nice size crack!

[Tbird1044]

Johnny:
Since you are down in the S.D. area, there is a really good guy down there that really knows these old TBirds. He owns a couple and also does repairs on them. His name is Ken Harkema and his website is http://kensklassic.com/ . Just thought I would pass this along.
Nyles

[knightrider]

Thanks tbird1044 I will check it out!!